Gear-cutting machine



Nov. 11 1924. 1,514,65i

F. BURGESS GEAR CUTTING MACHINE Filed Feb. 17. 1917 3 Sheets-Shet 1 Nov.11 1924.

F. BURGESS GEAR CUTTING MACHINE Filed Feb. 17. 7 3 Sheets-Sheet 3 Npv.

F. BURGESS GEAR CUTTING MACHINE Fi led Feb. 17 1917 3 Sheets-Sheet 3Patented Nov. ll, 1924i.

iitil tdi I arena sari;

GEAR-CUTTING MACHINE.

Application fi led February 17', 1923.. Serial No. 445,731.

To all whom it may concern.

Be it known that I, FRANK Bunenss, a

citizen of the United States, and resident of Quincy, county of Norfolk,Commonwealth of Massachusetts, have invented an Improve ment inGear-Cutting Machines, of which the following description, in connectionwith the accompanying drawings, is a specification, like characters onthe drawings representing like parts in each of the several views.

This invention relates more particularly to gear hobbing machines,though in a broader aspect being also applicable to milling machinesgenerally. A principal object of the invention is to provide a mountingfor the shaft bearing the hob or other outter, whereby the cutter as itextends for- Wa-rdly from the head over the work platen may be stronglyand rigidly supported approximately central of the platen, either projecting straight out from the head, or at any required angle according towhether the work in hand he the hobbing of spur gears or helical gearsof any desired angle. A further object is to provide a simplified andparticularly efficient distribution of power, for the work rotating andfeed movements and for the driving of the hob. The foregoing and otherobjects and advantages of the invention will more fully appear from thefollowing detailed description, and the distinctive features of noveltywill be pointed out in the appended claims.

Referring to the drawings:

Fig. 1 is a central vertical section of a gear hobbing machine embodyingthe invention;

Fig. 2 is a plan view thereof;

Fig. 3 is a partial vertical section of the mounting head for the hobshaft; and

Fig. at is a diagrammatic plan view illustrating the distribution ofpower from the prime drive shaft.

10 indicates the frame work and housing of the machine equipped at itsfront with ways on which is guided for vertical movement a knee 11,bearing a work-holding platen 12. At the top of the housing column 10, ahead plate 13 is mounted for sliding adjustment in parallelism with theplaten 12, and is adapted to be rigidly clamped in adjusted positionthereon by suitable clamping devices 14:. On this head plate a swivelhead 15 is mounted for angular adjustment and is adapted to be clampedrigidly -thereto in adjusted position by T-headed clamping bolts 16,engaging in a circular undercut slot of the head plate 13. The swivelhead 15 has journalled therein a shaft 17, projecting forwardlytherefrom and bearing a hob 18 extending over the platen 12. The shaft17 is driven by bevel gears 19 from a vertical shaft 20, the upper endof which is journalled in the plate 13, and the lower end of which isjournalled in a block 21 mounted for sliding adjustment on ways 22formed on an inward extension of the knee 11. The shaft 20 has one ormore key ways 23 formed therein, and is slidably keyed to abevel gear24- housed in the block 21 which meshes with another bevel gear25, fixedon a prime drive shaft 26. The shaft 26 has its outer portion journalledin a bushing block 27, which is clamped for vertical adjustment asindicated at 28 in a plate 29 which in turn is clamped for horizontaladjustment on the housing, as indicated at 30. The gear 24 has a hubportion equipped with a worm 31, which drives a worm gear 32 slidablykeyed on a shaft 33 horizontally journalled in the housing. This shaft33 serves to distribute power for rotating the work and for feeding thesame. For this purpose a train of gears 34: leads fromone end of thisshaft to a shaft 35 extending lengthwise of the platen and connected torotate the work by suitable means well understood in the art, and notshown herein, while the other end of the shaft is connected by a geartrain 36 to a feed screw 37 which operates the platen in suitable manneras well known in the art. Then the machine is to be used for cuttingspur gears, the hob shaft extends directly outward from the headaproximately central of the length of the platen as shown in full'linesin Figure 2. vl hen it is desired to cut spiral gears of any largeangle, the hob shaft is set at the required angle either to the right orto the left as indicated at a, Z) in Figure 2, and the head 13 is thenadjusted endwise, so as to bring the hob again approximately over thecenter of the platen as indicated at a o. I am thus enabled to locatethe hob or other rotary cutting element directly over the center of theplaten in any desired position of angular adjustment either to the rightor to the left whereby the hob and the workpiece are held and supportedmost strongly and rigidly with respect to each other, thus'minimizingchattering and possibilities of inaccuracy owing to looseness of anymember, insuring maximum smoothness and efiiciency in cutting the teeth.By the described construction I also provide for the distribution ofpower for rotating the hob and the workpiece, and the feed movement,with a minimum number of gears and shaft centers, thus minimizing thepossibility of inaccuracy owing to backlash and like causes. I am awarethat the invention may be embodied in other specific forms withoutdeparting from the spirit or essentialattributes thereof, and Itherefore desire the present embodiment to be considered in all respectsas illustrative and not restrictive, reference being had to the appendedclaims rather than to the foregoing description to indicate the scope ofthe invention.

Having described my invention, What I claim as new and desire to secureby LettersPatent is:

1. A gear cutting machine comprising a work holding platen presenting ahorizontally extending work-holding face, a horizontally extending shaftbearing a hob at its outer end extending substantially over Said platen,and a mounting for said shaft permitting angular adjustment thereof in ahorizontal plane and also bodily adj ustment laterally for permittinglocation of the hob substantially central of the platen irrespective ofthe angular adjustment thereof.

2. A gear cutting machine comprising a platen support for a work piece,a shaft bearing a hob at its outer end portion ex tending substantiallyover the work-holding face of said platen, and a mounting for said shaftpermitting angular adjustment thereof, in a plane parallel of saidwork-holding face and also rectilinear adjustment in parallelism withthe platen in a direction whereby the hob may be located centrally withrespect to the platen irrespective of angular adjustment thereof.

3. A gear cutting machine comprising a vertical shaft, a hob-bearingshaft in direct geared connection therewith and mounted for angularadjustment around said vertical shaft as an axis, with the hob bornethereby relatively remote from such axis, and a hori-v FRANK BURGESS.

